A belt retractor having an electrically actuatable locking device comprising a housing with a base plate and an upright first limb, a locking lever mounted pivotably on the upright first limb with a steel plate which is spring-loaded, and an electromagnet arranged in the housing and having a coil with a through opening, a first iron core which is arranged in the through opening, when a voltage is applied to the coil, exerts a magnetic force on the locking lever via the steel plate and actuates the locking lever for triggering a locking or unlocking movement against the force of the spring. The movement of the locking lever is enforced by a first magnetic circuit formed by the first iron core, the upright first limb and the portions of the base plate and of the locking lever between the first iron core and the upright first limb.